Would be awesome if these were all pins along one end - the board is quite wide on the breadboards I have, and it’s difficult to get access to the rows under it. (Would probably help with soldering this for newbies… like me :) )

this is for the jack that has magnetic(transformers) built in to protect the chip. This board works with the mag jack. The board you referred to works with a standard jack with no magnetic. As far as I know the pin out is spaced differently.

I have been successfully using this with an mbed, but what are the ‘gs1’ and ‘gs2’ pins? My guess is they have something to do with a ground (shielded ground?) but the RJ45 works without those pins. Can anyone tell me what they are?

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